Our aim is to discover whether, and how, variations in survey question format and wording affect response distributions and, especially, associations of response with other variables (for example, with education). We are also interested in constructing a classification of question types, as a way of locating such effects more precisely, and of developing a more general (but practically oriented) theory of how respondents are influenced by question wording. The project has proceeded by: (a) reviewing the literature on question wording, with later plans for a report on this review; (b) content analysing the types of questions included in four sets of national surveys over time; and (c), most centrally, carrying out sets of question experiments in national surveys. Early results make it clear that question wording can influence basic associations, as well as marginals, but such effects appear to vary by question type in ways presently being investigated. In addition, we are looking at how such question effects are influenced by intensity of opinion, by use of summary indices, and by a variety of other individual social variables, as well as attempting to determine which social categories of the population are most susceptible to question effects.